The most likely cause of fever in breast cancer patients after surgery is secondary infection. At this time, the patient needs to be treated with antibiotics. When appropriate antibiotics are used, the patient's fever will get better. The fever of some patients is caused by the absorbed heat after surgery. The body temperature of this absorbed heat is usually 38 ℃~38.5 ℃, which can be reduced by physical cooling. If necessary, a small amount of antipyretic drugs can be used for treatment. Patients with fever after breast cancer surgery should pay close attention to the wound healing, the color and status of the drainage fluid in the drainage tube, and give timely treatment.